package cn.tedu.v6;

import java.io.*;
import java.net.BindException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.*;

/**
 *  Version 5   登录与退出
 *  Version 6  在线用户列表：统计上线名称
 *                消息转发--交互--服务器客户端文字
 */
public class Server {
    private ServerSocket serverSocket;
    private static final Integer PORT = 7766;
    private List<PrintWriter> allOut=new ArrayList<>();
    //1.存储在线客户：onLineUsers
    private Set<String> onlineUsers= new HashSet<>();

    private Map<String,String> userDateBase;

    public Server() {
        try {
            serverSocket = new ServerSocket(PORT);
            //创建Map对象
            userDateBase=new HashMap<>();
            userDateBase.put("海燕","123456");
            userDateBase.put("小宝","654321");

        } catch (BindException e) {
            System.out.println("请检查端口号，被占用~");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void start() {
        try {
            while (true) {
                System.out.println("等待客户端连接");
                Socket socket = serverSocket.accept();

                new Thread(new ClientHandler(socket)).start();
            }
        } catch (IOException e) {
            System.out.println("客户端连接失败了");
        } finally {
            if (serverSocket != null && serverSocket.isClosed()) {
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    System.out.println("服务器关闭失败~~~");
                }
                System.out.println("服务器关闭成功~Over");
            }
        }
    }

    public static void main(String[] args) {
        new Server().start();
    }
    private synchronized void broadcastMessage(String message){
        for (PrintWriter pw:allOut){
            pw.println("消息广播："+message);
        }
    }
    //2.广播在线用户列表方法   updateOnLineUsers 更新在线人数
    // 提醒：没有参数，传入字符串保存所有的客户端名称
    //2.1 String userList="在线用户："+String.join(".",onlineUsers);
    //理解：拼接字符串，来一个客户名，记录一个客户端名
    //2.2 来一个客户端，分发一个客户端消息：用户名消息
    private synchronized void updateOnlineUser(){
        String userList ="在线用户："+ String.join("、",onlineUsers);
        broadcastMessage(userList);
    }


    private class ClientHandler implements Runnable {
        private Socket socket;
        private String ip;
        private PrintWriter pw;
        private BufferedReader br;

        private String username;
        private String password;

        public ClientHandler(Socket s) {
            this.socket = s;
            ip = socket.getInetAddress().getHostAddress();
            try {
                br = new BufferedReader(new InputStreamReader(socket.getInputStream(), "UTF8"));
                pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream(), "UTF8")), true);

            synchronized (allOut){
                allOut.add(pw);
            }
            } catch (IOException e) {
                System.out.println("客户端断开练习了~");
            }
        }

        private boolean Login(String user,String pass){

            return userDateBase.containsKey(
                    user)&&userDateBase.get(user).equals(pass);
        }
        private void handleChat(){
            new Thread(() -> {
                try {
                    String message;
                    while ((message = br.readLine()) != null) {
                        System.out.println(username + "客户端说：" + message);
                        System.out.print("服务器请输入：");
                        broadcastMessage(message);
                        if (message.equalsIgnoreCase("exit")) {
                            break;
                        }
                    }
                } catch (IOException e) {
                    System.out.println("客户端发来的消息断开了");
                }
            }).start();

            Scanner input = new Scanner(System.in);

            while (true) {
                System.out.println("服务器请输入：");
                String sme = input.nextLine();
                pw.println("服务器说：" + sme);

                if (sme.equalsIgnoreCase("exit")){
                    pw.println(username+"哈哈，我退了");
                    break;
                }
            }
        }
        public void run() {
            try {

        pw.println("请输入用户名");

        username=br.readLine();
        pw.println("请输入密码：");
        password=br.readLine();

        if (Login(username,password)){
            pw.println("登录成功，欢迎进入好运牌聊天室");
            //3.判断客户端链接成功---加入到集合当中    【3.1 同步块：监视对象--集合】
            //3.2 客户端登录成功-名字加入集合中  方法？
            synchronized (onlineUsers){
                onlineUsers.add(username);
                updateOnlineUser();
            }


            handleChat();
        }else{
            pw.println("登录失败，用户名或者密码错误！");
            socket.close();  //关闭
        }

            }catch(IOException e){
                System.out.println("服务器端读写出问题");
            } finally {
                //4. 同步块--从集合中依次移除用户名
                synchronized (onlineUsers){
                onlineUsers.remove(username);
                }

                synchronized (allOut) {//目的：移除，刚刚链接客户端
                    allOut.remove(pw);
                }

                if (pw != null)
                    pw.close();
                if (br != null)
                    try {
                        br.close();
                    } catch (IOException e) {
                        System.out.println("读入流断开连接");
                    }
                if (socket != null && !socket.isClosed()) {
                    System.out.println(username + "客户端退出服务器链接~");
                    try {
                        socket.close();
                    } catch (IOException e) {
                        System.out.println(username + "客户端退出链接异常~");
                    }
                }
            }
        }
    }
}